FLORA OF THE YELLOWSTONE NATIONAL PARK. 75 



PTERIDOPHYTA (Vascular Cryptogams). 



ISOET^. 



Isoetes Bolanderi, Etigelm. 



Muddy and gravelly b;>ttom of lakes and ponds tlirougliout, up to 

 9000 ft. alt. 



Isoetes pygmaea, Eiigelm.? 



Washed up on the shore of Yellowstone Lake, near mouth of Pelican 

 Creek. Probably deeply submerged. 



LYCOPODIACE^. 



Lycopodium annotinum, L. 



Dense woods. East Fork, 8500 ft. alt. Upper Falls of the Yel'.ow- 

 stone (Adams). Rare. 



RHIZOCARPEJE. 



Marsilia vestita, Hook, and Grev. 

 Yellowstone Lake (Coulter), 



OPHIOGLOSSACE^. 



Botrychium simplex, Hitchcock. 



Grassy meadows near mouth of Pelican Creek, 8000 ft. alt.; Yellow- 

 stone Park (Parry). Rare. 



Botrychium ternatum, Swartz, var. australe, Eaton. 



Rather common on hot spring and geyser formation throughout. 



FILTCES. 



Cryptogramme acrostichoides, R. Br. 



Rocky places. Slough Creek, 6700 ft. alt.; Obsidian Canon, 7700 ft. 

 alt.; Shoshone Lake and Lower Geyser Basin (Coulter). Local. 



Pteris aquilina, L. 



Dry open places, chiefly about the hot spring areas. 



Asplenium Filix-foemina, Bernh. 



Wooded cold springs at head of Broad Creek, 8200 ft. alt. 



Cystopteris fragilis, Bernh. 



Rather common in shaded rocky places. 



